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Update CComCoClass reference page #5211

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57 changes: 28 additions & 29 deletions docs/atl/reference/ccomcoclass-class.md
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Original file line number Diff line number Diff line change
@@ -1,40 +1,39 @@
---
description: "Learn more about: CComCoClass Class"
title: "CComCoClass Class"
description: "Learn more about: CComCoClass Class"
ms.date: "11/04/2016"
f1_keywords: ["CComCoClass", "ATLCOM/ATL::CComCoClass", "ATLCOM/ATL::CComCoClass::CreateInstance", "ATLCOM/ATL::CComCoClass::Error", "ATLCOM/ATL::CComCoClass::GetObjectCLSID", "ATLCOM/ATL::CComCoClass::GetObjectDescription"]
helpviewer_keywords: ["CComCoClass class", "aggregation [C++], aggregation models"]
ms.assetid: 67cfefa4-8df9-47fa-ad58-2d1a1ae25762
---
# CComCoClass Class

This class provides methods for creating instances of a class, and obtaining its properties.

## Syntax

```
```cpp
template <class T, const CLSID* pclsid = &CLSID_NULL>
class CComCoClass
```

#### Parameters

*T*<br/>
*T*\
Your class, derived from `CComCoClass`.

*pclsid*<br/>
*pclsid*\
A pointer to the CLSID of the object.

## Members

### Public Methods

|Name|Description|
|----------|-----------------|
|[CComCoClass::CreateInstance](#createinstance)|(Static) Creates an instance of the class and queries for an interface.|
|[CComCoClass::Error](#error)|(Static) Returns rich error information to the client.|
|[CComCoClass::GetObjectCLSID](#getobjectclsid)|(Static) Returns the object's class identifier.|
|[CComCoClass::GetObjectDescription](#getobjectdescription)|(Static) Override to return the object's description.|
| Name | Description |
| ---------------------------------------------------------- | ----------------------------------------------------------------------- |
| [CComCoClass::CreateInstance](#createinstance) | (Static) Creates an instance of the class and queries for an interface. |
| [CComCoClass::Error](#error) | (Static) Returns rich error information to the client. |
| [CComCoClass::GetObjectCLSID](#getobjectclsid) | (Static) Returns the object's class identifier. |
| [CComCoClass::GetObjectDescription](#getobjectdescription) | (Static) Override to return the object's description. |
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Should we format tables as well, to improve readability of the raw markdown source?

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Good question. I see benefits both ways. I usually don't because it becomes maintenance to keep it that way. As the owner of 10,000 topics I try to reduce maintenance whenever I can.

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I would think maintenance becomes a factor for tables that update somewhat frequently. Most of these tables never really change in 5+ years, so it might be worth formatting it once and keeping it as such.

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It depends on the font in your editor whether the cleaned up version looks cleaned up. And we have editor tools that actually do the opposite and remove all the spaces from tables. I see both versions in our docs. I can see the value both ways. But mostly, I'd prefer not to spend time on PRs that clean up tables because its time I can't really afford for a gain that is nebulous in the scheme of things.
I very much appreciate all the other contributions you make because they add clear customer value and are things I'd have to do myself. You've made ongoing and significant improvements to these docs, for which I thank you.

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Noted! Will not format tables in future PRs since there might not be a clear benefit (with potential downsides).


## Remarks

Expand All @@ -58,23 +57,23 @@ You can override either of these defaults by specifying another macro in your cl

Use these `CreateInstance` functions to create an instance of a COM object and retrieve an interface pointer without using the COM API.

```
template <class Q>
static HRESULT CreateInstance( Q** pp);
```cpp
template <class Q>
static HRESULT CreateInstance(Q** pp);

template <class Q>
template <class Q>
static HRESULT CreateInstance(IUnknown* punkOuter, Q** pp);
```

### Parameters

*Q*<br/>
*Q*\
The COM interface that should be returned via *pp*.

*punkOuter*<br/>
*punkOuter*\
[in] The outer unknown or controlling unknown of the aggregate.

*pp*<br/>
*pp*\
[out] The address of a pointer variable that receives the requested interface pointer if creation succeeds.

### Return Value
Expand All @@ -101,7 +100,7 @@ In the following example, `CDocument` is a wizard-generated ATL class derived fr

This static function sets up the `IErrorInfo` interface to provide error information to the client.

```
```cpp
static HRESULT WINAPI Error(
LPCOLESTR lpszDesc,
const IID& iid = GUID_NULL,
Expand Down Expand Up @@ -130,7 +129,7 @@ static HRESULT WINAPI Error(
UINT nID,
const IID& iid = GUID_NULL,
HRESULT hRes = 0,
HINSTANCE hInst = _AtlBaseModule.GetResourceInstance ());
HINSTANCE hInst = _AtlBaseModule.GetResourceInstance());

static HRESULT Error(
UINT nID,
Expand All @@ -143,25 +142,25 @@ static HRESULT Error(

### Parameters

*lpszDesc*<br/>
*lpszDesc*\
[in] The string describing the error. The Unicode version of `Error` specifies that *lpszDesc* is of type LPCOLESTR; the ANSI version specifies a type of LPCSTR.

*iid*<br/>
*iid*\
[in] The IID of the interface defining the error or GUID_NULL (the default value) if the error is defined by the operating system.

*hRes*<br/>
*hRes*\
[in] The HRESULT you want returned to the caller. The default value is 0. For more details about *hRes*, see Remarks.

*nID*<br/>
*nID*\
[in] The resource identifier where the error description string is stored. This value should lie between 0x0200 and 0xFFFF, inclusively. In debug builds, an **ASSERT** will result if *nID* does not index a valid string. In release builds, the error description string will be set to "Unknown Error."

*dwHelpID*<br/>
*dwHelpID*\
[in] The help context identifier for the error.

*lpszHelpFile*<br/>
*lpszHelpFile*\
[in] The path and name of the help file describing the error.

*hInst*<br/>
*hInst*\
[in] The handle to the resource. By default, this parameter is `_AtlModule::GetResourceInstance`, where `_AtlModule` is the global instance of [CAtlModule](../../atl/reference/catlmodule-class.md).

### Return Value
Expand All @@ -178,7 +177,7 @@ If the *hRes* parameter is nonzero, then `Error` returns the value of *hRes*. If

Provides a consistent way of retrieving the object's CLSID.

```
```cpp
static const CLSID& WINAPI GetObjectCLSID();
```

Expand All @@ -190,7 +189,7 @@ The object's class identifier.

This static function retrieves the text description for your class object.

```
```cpp
static LPCTSTR WINAPI GetObjectDescription();
```

Expand Down